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This work discovers that Cu 2 O nanocrystals with controllable structures can be synthesized on surfaces of nanoporous Cu and amorphous ribbons by free dealloying of Cu-based amorphous alloys in acidic solutions. Technological parameters, such as the acid, acid concentration, and dealloying time strongly influence the crystal size, structure and morphology of Cu 2 O. Cu 2 O nanocubes are fabricated on surfaces of nanoporous Cu in the hydrofluoric acid treated alloy, while various Cu 2 O particles are tailored on surfaces of amorphous alloys immersed in hydrochloric acid for different time. The increasing dealloying time and adsorbed oxygen improve the growth rates along the 1 0 0 direction of Cu 2 O crystals relative to that of the 1 1 1 direction, which is the key to change the shapes of Cu 2 O crystals. The understanding of morphology evolution of Cu 2 O nanocrystals in this work is helpful in tailoring Cu 2 O particles with designable shapes and controllable properties in application fields.

This paper reviews the influence of alloying elements Mo, Nb, Ta and Ni on glass formation and corrosion resistance of Cu-based bulk metallic glasses (BMGs). In order to obtain basic knowledge for application to the industry, corrosion resistance of the Cu–Hf–Ti–(Mo, Nb, Ta, Ni) and Cu–Zr–Ag–Al–(Nb) bulk glassy alloy systems in various solutions are reported in this work. Moreover, X-ray photoelectron spectroscopy (XPS) analysis is performed to clarify the surface-related chemical characteristics of the alloy before and after immersion in the solutions; this has lead to a better understanding of the correlation between the surface composition and the corrosion resistance.

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We have successfully synthesized multicomponent Mg-based nano-quasicrystals (nano-QCs) through a simple route by using a water-cooled wedge-shaped copper mould. Nanoscale QCs are prepared directly on tip of wedge-shaped castings. The further study shows that nano-QCs in the Mg71Zn26Y2Cu1alloy show well microhardness of greater than HV450. Electrochemical properties of three kinds of quasicrystal alloys are investigated in simulated seawater. The Mg71Zn26Y2Cu1nano-QC alloy presents the best corrosion resistance in this study for the formation of well-distributed nano-QC phases (1~5 nm) and polygonal Mg2(Cu,Y) nanophases (40~50 nm).